Alphabet’s Google escaped a breakup of its advertising technology business on Sept 2, marking the third time in recent years that US antitrust enforcers have tried to force a Big Tech breakup and lost.

US Judge Leonie Brinkema in Alexandria, Virginia, declined to make Google sell AdX, where publishers pay Google a 20 per cent fee to sell ads in auctions that happen instantly when users load websites. The Department of Justice (DOJ) had argued Google could not be trusted to run the online advertising exchange after Brinkema ruled that Google had illegally quashed competition.

The judge accepted behavioural remedies. She will release a detailed ruling in 14 days to give time to redact confidential information. Google had proposed fixes including providing real-time bid access to competitors.

The ruling fuelled questions about whether courts are up to the task of checking the industry’s unprecedented power over the US economy, and the fate of a crackdown that started during President Donald Trump’s first term.

Cases against Amazon and Apple involving smartphone and online retail markets have not yet gone to trial. And while two judges found Google engaged in anticompetitive conduct in separate markets, they rejected the strongest measure of requiring it to sell assets.

AdX is a small part of Google’s business. Google shares pared gains slightly after the ruling and were up 0.6 per cent.

Google welcomed the court decision. “We’re very pleased the Court rejected the DOJ’s proposal to break apart tools that help small businesses reach new customers and grow,” said executive Lee-Anne Mulholland.

The DOJ is “pleased that the court ordered substantial relief,” it said in a social media post on X.

“We are one step closer to resto...